Guide to Computer Forensics
and Investigations
Fourth Edition
Chapter 16
Ethics for the Expert Witness
Objectives
• Explain how ethics and codes apply to expert
witnesses
• Explain how other organizations’ codes of ethics
apply to expert testimony
• Describe ethical difficulties in expert testimony
• Explain the process of carving data manually
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Applying Ethics and Codes to Expert
Witnesses
• Ethics
– Rules you internalize and use to measure your
performance
• Codes of professional conduct or responsibility
– Standards that others apply to you or that you are
compelled to adhere to by external forces
• Such as licensing bodies
• People need ethics to help maintain their balance
– And self-respect and the respect of their profession
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Applying Ethics and Codes to Expert
Witnesses (continued)
• Laws governing codes of professional conduct or
responsibility
– Define the lowest level of action or performance
required to avoid liability
• Expert witnesses should present unbiased,
specialized, and technical evidence to a jury
• Expert witnesses testify in more than 80% of trials
– And in many trials, multiple expert witnesses testify
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Applying Ethics and Codes to Expert
Witnesses (continued)
• The most important laws applying to attorneys and
witnesses are the rules of evidence
• Experts are bound by their own personal ethics and
the ethics of their professional organizations
• In the United States, there’s no state or national
licensing body for computer forensics examiners
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Computer Forensics Examiners’ Roles
in Testifying
• Computer forensics examiners have two roles:
– Scientific/technical witness and expert witness
• As expert witness
– You can testify even if you weren’t present when the
event occurred
• Or didn’t handle the data storage device personally
• Criticism: it’s possible to find and hire an expert to
testify to almost any opinion on any topic
– Beware of attorneys’ opinion shopping
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Considerations in Disqualification
• One of the effects of violating court rules or laws is
disqualification
• Opposing counsel might attempt to disqualify you
– Based on any deviations from opinions you’ve given
in previous cases
• Some attorneys contact many experts as a ploy to
disqualify them
– Or prevent opposing counsel from hiring them
• Determine who the parties are to reduce the
possibility of a conflict
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Considerations in Disqualification
(continued)
• Whenever you are aware of a possible
disqualification issue
– Bring it to the attention of the attorney who has
retained you
• Factors to disqualify an expert include:
– Whether the attorney informed the expert that their
discussions were confidential
– Whether the expert reviewed materials marked as
confidential or attorney work product
– Whether the expert was asked to sign a
confidentiality agreement
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Considerations in Disqualification
(continued)
• Factors to disqualify an expert include: (continued)
–
–
–
–
Number of discussions held over a period of time
The type of documents that were reviewed
The type of information conveyed to the expert
The amount of time involved in discussions or
meetings between the expert and attorney
– Whether the expert provided the attorney with
confidential information
– Whether the attorney formally retained the expert
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Considerations in Disqualification
(continued)
• Factors to disqualify an expert include: (continued)
– Whether the expert voiced concerns about being
retained
– Whether the expert was requested to perform
services for the attorney
– Whether the attorney compensated the expert
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Traps for Unwary Experts
• Be cautious about the following potential traps
– What are some differences between the attorney’s
motives and the investigator’s duty?
– Is the function of the expert witness in conflict with
the investigator’s code of professional responsibility?
– You should anticipate that the opposing counsel will
look at your organization memberships and those
organizations’ codes of professional responsibility
• Contingency fees aren’t allowed except in certain
limited circumstances
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Traps for Unwary Experts (continued)
• Avoid obvious ethical errors
–
–
–
–
–
Don’t present false data or alter data
Don’t report work that was not done
Don’t ignore available contradictory data
Don’t do work beyond your expertise or competence
Don’t allow the attorney who retained you to
influence your opinion in an unauthorized way
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Traps for Unwary Experts (continued)
• Avoid obvious ethical errors (continued)
– Don’t accept an assignment if it cannot reasonably
be done in the allowed time
– Don’t reach a conclusion before you have done
complete research
– Don’t fail to report possible conflicts of interest
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Determining Admissibility of Evidence
• Hypothetical questions can give you the factual
structure to support and defend your opinion
• Although expert opinions can be presented without
stating the underlying factual basis
– The testimony isn’t admissible if the facts on which
the opinion is based are inadequate
– Or there’s insufficient evidence to allow stating a
legitimate opinion
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Organizations with Codes of Ethics
• No single source offers a definitive code of ethics
for expert witnesses
• You must draw on standards from other
organizations to form your own ethical standards
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International Society of Forensic
Computer Examiners
• Includes guidelines such as the following:
– Maintain the utmost objectivity in all forensic
examinations and present findings accurately
– Conduct examinations based on established,
validated principles
– Testify truthfully in all matters before any board,
court, or proceeding
– Avoid any action that would appear to be a conflict of
interest
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International Society of Forensic
Computer Examiners (continued)
• Includes guidelines such as the following:
(continued)
– Never misrepresent training, credentials, or
association membership
– Never reveal any confidential matters or knowledge
learned in an examination without an order from a
court of competent jurisdiction or the client’s express
permission
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International High Technology Crime
Investigation Association
• HTCIA core values include the following
requirements related to testifying:
– The HTCIA values the Truth uncovered within digital
information and the effective techniques used to
uncover that Truth, so that no one is wrongfully
convicted
– The HTCIA values the Integrity of its members and
the evidence they expose through common
investigative and computer forensic best practices,
including specialized techniques used to gather
digital evidence
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International Association of Computer
Investigative Specialists
• Standards for IACIS members include:
– Maintain the highest level of objectivity in all forensic
examinations and accurately present the facts
involved
– Thoroughly examine and analyze the evidence
– Conduct examinations based upon established,
validated principles
– Render opinions having a basis that is
demonstratively reasonable
– Not withhold any findings that would cause the facts
of a case to be misrepresented or distorted
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American Bar Association
• Be aware of the basic rules of professional conduct
attorneys must follow
• ABA’s Model Code of Professional Responsibility
(Model Code) and its successor, the Model Rules
of Professional Conduct (Model Rules)
– Are the basis of state licensing bodies’ codes
• Codes contain provisions limiting the fees experts
can receive for their services
• The ABA has stated that expert witnesses do not
owe a duty of loyalty to their clients
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American Medical Association
• Sets out five recommendations:
– The physician is a professional with special training
and experience and has an ethical obligation to
assist the administration of justice
– The physician may not become a partisan during the
legal proceeding
– The medical witness should testify truthfully and be
adequately prepared
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American Medical Association
(continued)
• Sets out five recommendations: (continued)
– The physician must make the attorney calling him or
her aware of favorable and unfavorable information
uncovered in the physician’s assessment
– The physician may not accept a contingency fee
• Several other provisions address the ethical
constraints of testifying physicians
• The AMA also sets goals in dealing with its
members
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American Psychological Association
• APA’s Ethical Principles of Psychologists and Code
of Conduct
– The most broadly accepted set of guidelines
governing psychologists’ conduct as experts
• Several standards in the APA’s Ethics Code apply
to psychologists’ expert testimony
• The Ethics Code also cautions psychologists about
the limitations of assessment tools
• Other Ethics Code standards are related to expert
testimony, too
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Ethical Difficulties in Expert Testimony
• There are inherent conflicts between the goals of
attorneys
– And the goals of scientists or technicians (experts)
• Attorneys work in an adversarial system and look
to sway the judge or jury
• Science requires experts to focus on the evidence
without the influence of others’ objectives
• Daubert and the APA’s forensics guidelines
– Can challenge experts to choose between complete
impartiality and responsible advocacy
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Ethical Difficulties in Expert Testimony
(continued)
• Enforcing any professional organization’s ethical
guidelines is difficult
– Principles can be enforced only against members of
the organization
• All guidelines rely primarily on internalization of the
codes and witnesses’ analysis of when and how
they will participate in a case
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Ethical Responsibilities Owed to You
• Your attorney owes you
– A fair statement of the case or situation
– Adequate time to review evidence and prepare your
report
– A reasonable opportunity to examine data, conduct
testing, and investigate the matter before rendering
an opinion
• Most attorneys, including opposing counsel, are
competent, courteous professionals
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Ethical Responsibilities Owed to You
(continued)
• Some opposing counsel attempt to make discovery
depositions physically uncomfortable
• As a measure of protection, you might want to have
your personal attorney attend the deposition
– This attorney can’t object to questions but is
available to advise the attorney who retained you or
to advise you during breaks
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Standard and Personally Created
Forensics Tools
• The tools you use to recover, control, and track
evidence are subject to review by opposing parties
– If the court deems them unreliable, the evidence you
recovered with those tools might not be admitted
• Or might be admitted with a limiting instruction
• If you use standard tools, you simplify the process
of validating them
• Personally created tools might have advantages
that you can demonstrate to a judge
– Who determines whether evidence is admissible
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Summary
• Ethics can be defined as rules you internalize and
use to measure your performance
• There’s no U.S. licensing body for computer
forensics examiners
• Be aware of attempts to disqualify you as an expert
• Courts use many factors in determining whether to
disqualify an expert
• Be aware of obvious ethical errors
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Summary (continued)
• No single source offers a definitive code of ethics
for expert witnesses
• The inherent conflict between the needs of the
justice system and your obligations for professional
conduct can create ethical difficulties
• The attorney who has retained you, opposing
counsel, and the court owe you ethical
responsibilities as an expert witness
• The tools you use to recover, control, and track
evidence are subject to review by opposing parties
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Summary (continued)
• After carving data artifacts, analyzing as much of
the information as possible is critical